Disposable capsules useful to maintain coreactive components, are known in the art. For example, dental capsules containing amalgam precursors as mercury and silver or silver alloy are well known. In all of the prior art disposable capsules, a manipulative step must be carried out prior to mixing the coreactive components.
It would be very desirable to eliminate any such manipulative step and especially in the dental art it would be desirable to have a dental capsule containing the dental amalgam precursors from which a dental amalgam could be prepared merely by placing such capsule into an amalgamator.
Examples of prior art of disposable capsules include capsules having rupturable membranes and means for rupturing said membranes prior to mixing of coreactive components. For example, U.S. Pat. No. 3,451,540 teaches a disposable capsule comprising a telescoping cylinder which is activated by sliding the separate section together to rupture the membrane which divides the capsule into two chambers and thereby allow the coreactants maintained separate in such chambers to mix. Similar capsules are disclosed in U.S. Pat. No. 3,625,349 and U.S. Pat. No. 3,595,439 wherein the membrane is in the form of a pouch, containing a coreactant and such pouch is ruptured by either squeezing through a rotating mechanism or a sliding mechanism until it bursts. See also U.S. Pat. Nos. 3,907,106, 3,860,114, 3,841,467, 3,831,742, 3,655,035, 3,638,918, 3,756,571, 1,774,258 for similar capsules.
Disposable capsules which utilize a removable plug to isolate the coreactive components and which plug is removed to allow such components to mix are also known in the art. See for example U.S. Pat. No. 3,275,302, wherein a ball or a disc is positioned to divide the capsule into two chambers each containing a coreactive component. This capsule is activated by turning the capsule upside down to dislodge the ball or disc. See also U.S. Pat. Nos. 3,796,303, 3,809,225, 2,527,992, 2,527,991 and 3,785,481 for other capsules utilizing removable plugs.
Other disposable capsules rely on a passageway between the two chambers which passageway can be closed and opened by either twisting, sliding or unscrewing one or more sections of the capsule. For example, in U.S. Pat. No. 3,357,545 the top of the capsule is unscrewed to remove a stem on the upper section of said capsule from a conduit in the lower section. Removal of such stem allows the coreactive component maintained in the upper section to fall into the lower section. Also see U.S. Pat. Nos. 3,139,180, 3,139,181, 3,917,062, 3,963,120 and 3,924,741 for similar capsules.
It is thus clear that unlike the instant disposable capsule, the prior art capsules require some manipulative step prior to the step of mixing the coreactive components.